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Treub. — Some words on 
of the first things wanted is the complete embryology of 
Lycopodium cernuum or of an allied form. An exact know- 
ledge of the development of this embryo is particularly 
required, after the publication of Professor Bower’s interesting 
memoir on Phylloglossum Drummondii. Professor Bower’s 
comparison of the adult Phylloglossum with the young Ly- 
copod, a theoretical view expressed also by Mr. Bertrand of 
Lille, may find new support as soon as the embryology of L. 
cernuum is completely known. Last year I collected upwards 
of a hundred prothalli of L. cernuum in order to continue my 
researches on the embryo, but I was unsuccessful. The form 
of these prothalli makes the investigation of the embryo- 
development exceedingly difficult. I intend to try again as 
soon as I return to Java. Perhaps the prothalli I have 
described of the form allied to L. densum will give a better 
chance of success. 
A second point to be investigated is the mode of vegetative 
propagation of L. cernuum. In this species the root-tops 
change into propagating organs of a remarkable form. These 
root-gemmae or bulbs produce on germinating young plants 
very much like those which come forth from prothalli. For 
several reasons I anticipate that the study of these gemmae, 
their formation and germination, will give interesting results. 
I have collected a sufficient amount of material during the 
last two years, and before long I hope to work out this subject. 
A third desideratum is knowledge of the prothallus of 
Psilotum . It is to be feared this will remain a desideratum 
for a very long time. Although I have trained myself in 
finding young plants and prothalli of Lycopodiaceae in the 
forests, and especially on trees, I have never succeeded with 
Psilotum , although there are parts of our Java forests where 
Psilotum Jlaccidum , Wall., is not at all rare. After all, it is not 
impossible that prothalli of Psilotum are nowadays nowhere 
to be found, Count de Solms-Laubach’s researches having 
made known the existence of organs, bulbils or gemmae, 
propagating the asexual generation of Psilotum even in 
European hothouses. 
